Process of retinning bath-tubs



7 UNITED STATES PATENT OFFICE.

DAWSON B. HILTON, OF BROOKLYN, !NEW YORK.

PROCESS OF RETINNING .BATH-TUBS.

SPECIFICATION formingpart of Letters Patent No. 526,836, dated October2, 1894.

Application filed. June 8,1894. Serial No. 513,924:- (No p ns) cess bywhich bath tubs composed of copper,

sheet iron or zinc may be retinned without removing the bath tubs ordisturbing the plumbing or woodwork.

Heretofore it has been impracticable to retin bath tubs withoutdetaching and removing them, because the solder would run unevenly overthe surface and the tub had to be tilted, to spread the solderuniformly. By my invention, the solder runs entirely smooth while thebath tub may be retained in its normal upright position.

In carrying out my invention I proceed as follows: The bath tub isscoured with coarse sand and raw muriatic acid, to remove the dirt,grease and stains; the sand and acid are washed off by water, and-a bathof raw muriatic acid is applied- Next I cover the bath tub with a liquidalloy which acts as a flux, and which is composed of about two-thirdsparts of mercury and one-third part of a soft metal which is dissolvablein mercury. For this metal, I prefer to use pure tin filings, thoughlead, Babbitt metal, pewter, or other .soft metals may be used. Afterthe tub is thoroughly bright with this alloy, I clean off the scum withwater, and then apply a bath of nitric acid, which I let stand until awhite cleaned ofi with sand, and the sand is washed off by water, andthen the process is completed.

I have found in practice, that by my improved process, the solder can bedistributed evenly over the entire surface of the tub, and that it willnot form lumps or ridges, while the soldering iron need be heated onlyto such an extent, that it will not warp the body of the tub.

What I claim is The process of re-tinning bath tubs which consists inwashing them with acid, applying an alloy consisting of mercury and asoft metal dissolved therein, washing consecutively with nitric andmuriatic acid, applying a coating of solder, washing with muriatic acid,and applying a second coating of solder, substantially as specified.

DAwsoN B. HILTON. Witnesses:

F. v. BEIEsEN, WILLIAM SOHULZ.

